Exploring Nonbattle Injury in the Deployed Military Environment Using the Department of Defense Trauma Registry

David S Kauvar, Jennifer Gurney

Mil Med 2020 Mar 7; Online ahead of print.

Abstract

Introduction: The impact of disease and nonbattle injury (DNBI) on casualty burden of military operations has historically been greater than that of battle-related injuries. The ratio of battle to DNBI casualties has changed as advances in equipment, hygiene, and infectious diseases have been made; however, during military operations in Iraq and Afghanistan, 30% of serious injuries treated or evacuated from the area of operations were secondary to NBI. Most DoD research and intervention efforts focus on battle injuries; NBI has received much less practical attention. We aimed to explore the potential utility of the largest Department of Defense casualty database in identifying potential intervention targets for preventing NBI events.

Materials and methods: Phase I was a comprehensive NBI literature review from historical and current military operations. Phase II was an IRB exempt initial examination of relevant data contained in the Department of Defense Trauma Registry (DoDTR). Phase I: A MEDLINE search using the terms "military", "injury", and "nonbattle/non battle" was performed, and articles containing useful data points to characterize the unique risks of the modern deployed military environment and identify potentially preventable NBI hazards in the modern deployed military environment were retrieved and reviewed in full-text. Phase II: This information was used to explore data within the DoDTR's and its ability to provide data to inform NBI prevention efforts in the following areas: most prevalent NBI causes, NBI location and timing related to operational tempo, characteristics of the population at risk for NBI.

Results: Phase I: Falls and motor vehicle crashes (MVCs) accounted for most of the serious NBI in Iraq and Afghanistan. No specific epidemiologic data was readily available to guide NBI prevention efforts. Phase II was limited to NBI and falls from Iraq and Afghanistan in the DoDTR. Only aggregate data were available with a total of 1829 falls and 1899 MVCs. Case fatality for falls was 1.1% and for MVCs 6.5%. The greatest frequency of NBI was in Iraq among

U.S. Army personnel, but comparison of rates is not possible without reliable denominators for individual variables. Annual NBI incidence seems proportional to overall level of personnel deployed to each theater, but without knowledge of the true denominator of total deployed personnel, it is impossible to conclude definitively. The annual number of falls was stable throughout the period of highest operational tempo in Iraq (2003-2011), although MVCs were more common earlier in the operation (2003-2005), likely corresponding to greater operational maneuver.

Conclusions: The deployed military environment is dangerous and NBI presents a primary prevention target for expeditionary operations. The DoDTR is a database of detailed injury and medical care information and lacks much of the data required to perform a comprehensive epidemiologic NBI analysis. Specific prevention recommendations cannot be made based solely on DoDTR data and integration with other DoD databases that assess operational and tactical data should be considered.